path: root/drivers/s390/cio/cio.c

/*
 *  drivers/s390/cio/cio.c
 *   S/390 common I/O routines -- low level i/o calls
 *
 *    Copyright IBM Corp. 1999,2008
 *    Author(s): Ingo Adlung (adlung@de.ibm.com)
 *		 Cornelia Huck (cornelia.huck@de.ibm.com)
 *		 Arnd Bergmann (arndb@de.ibm.com)
 *		 Martin Schwidefsky (schwidefsky@de.ibm.com)
 */

#define KMSG_COMPONENT "cio"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt

#include <linux/ftrace.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/device.h>
#include <linux/kernel_stat.h>
#include <linux/interrupt.h>
#include <asm/cio.h>
#include <asm/delay.h>
#include <asm/irq.h>
#include <asm/irq_regs.h>
#include <asm/setup.h>
#include <asm/reset.h>
#include <asm/ipl.h>
#include <asm/chpid.h>
#include <asm/airq.h>
#include <asm/isc.h>
#include <asm/cputime.h>
#include <asm/fcx.h>
#include <asm/nmi.h>
#include <asm/crw.h>
#include "cio.h"
#include "css.h"
#include "chsc.h"
#include "ioasm.h"
#include "io_sch.h"
#include "blacklist.h"
#include "cio_debug.h"
#include "chp.h"

debug_info_t *cio_debug_msg_id;
debug_info_t *cio_debug_trace_id;
debug_info_t *cio_debug_crw_id;

/*
 * Function: cio_debug_init
 * Initializes three debug logs for common I/O:
 * - cio_msg logs generic cio messages
 * - cio_trace logs the calling of different functions
 * - cio_crw logs machine check related cio messages
 */
static int __init cio_debug_init(void)
{
	cio_debug_msg_id = debug_register("cio_msg", 16, 1, 16 * sizeof(long));
	if (!cio_debug_msg_id)
		goto out_unregister;
	debug_register_view(cio_debug_msg_id, &debug_sprintf_view);
	debug_set_level(cio_debug_msg_id, 2);
	cio_debug_trace_id = debug_register("cio_trace", 16, 1, 16);
	if (!cio_debug_trace_id)
		goto out_unregister;
	debug_register_view(cio_debug_trace_id, &debug_hex_ascii_view);
	debug_set_level(cio_debug_trace_id, 2);
	cio_debug_crw_id = debug_register("cio_crw", 16, 1, 16 * sizeof(long));
	if (!cio_debug_crw_id)
		goto out_unregister;
	debug_register_view(cio_debug_crw_id, &debug_sprintf_view);
	debug_set_level(cio_debug_crw_id, 4);
	return 0;

out_unregister:
	if (cio_debug_msg_id)
		debug_unregister(cio_debug_msg_id);
	if (cio_debug_trace_id)
		debug_unregister(cio_debug_trace_id);
	if (cio_debug_crw_id)
		debug_unregister(cio_debug_crw_id);
	return -1;
}

arch_initcall (cio_debug_init);

int cio_set_options(struct subchannel *sch, int flags)
{
	struct io_subchannel_private *priv = to_io_private(sch);

	priv->options.suspend = (flags & DOIO_ALLOW_SUSPEND) != 0;
	priv->options.prefetch = (flags & DOIO_DENY_PREFETCH) != 0;
	priv->options.inter = (flags & DOIO_SUPPRESS_INTER) != 0;
	return 0;
}

static int
cio_start_handle_notoper(struct subchannel *sch, __u8 lpm)
{
	char dbf_text[15];

	if (lpm != 0)
		sch->lpm &= ~lpm;
	else
		sch->lpm = 0;

	CIO_MSG_EVENT(2, "cio_start: 'not oper' status for "
		      "subchannel 0.%x.%04x!\n", sch->schid.ssid,
		      sch->schid.sch_no);

	if (cio_update_schib(sch))
		return -ENODEV;

	sprintf(dbf_text, "no%s", dev_name(&sch->dev));
	CIO_TRACE_EVENT(0, dbf_text);
	CIO_HEX_EVENT(0, &sch->schib, sizeof (struct schib));

	return (sch->lpm ? -EACCES : -ENODEV);
}

int
cio_start_key (struct subchannel *sch,	/* subchannel structure */
	       struct ccw1 * cpa,	/* logical channel prog addr */